1. Field of the Invention
The present invention relates to a developer cartridge to be detachably mounted into an apparatus main body of an image forming apparatus and an image forming apparatus with the developer cartridge.
2. Description of the Related Art
A developer cartridge is for supplying developer to a developing device housed in an apparatus main body of an image forming apparatus. The developer cartridge filled with the developer is detachably mounted into the apparatus main body with a door disposed at a specified position of the apparatus main body opened. The mounted developer cartridge is replaced with a new one when being emptied due to the consumption of the developer by image forming processes and then the opened door is closed.
A known developer cartridge is formed at the bottom of a cartridge main body with a supply port for supplying developer, and a shutter member for opening and closing the supply port is provided in the cartridge main body. Further, an operation lever for opening and closing operations of the shutter member is provided outside the cartridge main body.
When such a developer cartridge is mounted into the apparatus main body of the image forming apparatus, the operation lever is operated to supply the developer to the developing device. By this operation, the shutter member is opened and the developer in the cartridge main body can be supplied to the developing device through the supply port.
However, with the conventional developer cartridge, the supply port cannot be opened by moving the shutter member in a closed state unless a user manually operates the operation lever after the developer cartridge is mounted into the apparatus main body of the image forming apparatus. Accordingly, as in the case where the user forgot to operate the operation lever at the time of mounting the developer cartridge into the apparatus main body, there may occur such an inconvenience that the door is closed with the shutter member left closing the supply port and the image forming process is performed in this state.
In order to solve such an inconvenience, a developer cartridge according to a first prior art includes a sensor for detecting an opened/closed state of a supply port and the detection result of this sensor is output. In this case, a user can check whether or not an operation lever has been operated by seeing the detection result.
On the contrary, a developer cartridge according to a second prior art is so constructed that a specified interference member interferes with a door and the door cannot be closed unless an operation lever is operated. This enables a user to learn that the operation lever has not been operated.
However, for the developer cartridge according to the first prior art, it is necessary to additionally provide the sensor for detecting the operation of the operation lever and a notifier for notifying the detection result of the sensor, which presents a problem of increasing the number of parts and the cost of the apparatus. With the developer cartridge according to the second prior art, it can be learned that the operation of the operation lever was forgotten if the door cannot be closed. However, after learning that, the user has to open the door and operate the operation lever. Thus, it is very cumbersome for the user.